Investments and Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash and short-term investments	$ 1,035		$ 850
Level 1 to Level 2 transfer amount	56
Corporate Obligations [Member] | Maturity Dates Exceeding One Year [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	2,100
Bank Notes/Certificates of Deposit/Time Deposits [Member] | Maturity Dates Exceeding One Year [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	250
Government Agency Investments [Member] | Maturity Dates Exceeding One Year [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	511
Estimate of Fair Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	8,111	[1],[2]
Restricted cash and short-term investments	1,035	[1]
Fuel derivative contracts, net	109	[1]
Fair value of assets and liabilities measured on recurring basis	9,255
Estimate of Fair Value Measurement [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	3,071	[1],[2]
Estimate of Fair Value Measurement [Member] | US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	1,512	[1],[2]
Estimate of Fair Value Measurement [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	170	[1],[2]
Estimate of Fair Value Measurement [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	2,750	[1],[2]
Estimate of Fair Value Measurement [Member] | Bank Notes/Certificates of Deposit/Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	608	[1],[2]
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	3,071	[1],[2]
Restricted cash and short-term investments	979	[1]
Fuel derivative contracts, net	0	[1]
Fair value of assets and liabilities measured on recurring basis	4,050
Level 1 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	3,071	[1],[2]
Level 1 [Member] | US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Level 1 [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Level 1 [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Level 1 [Member] | Bank Notes/Certificates of Deposit/Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	5,040	[1],[2]
Restricted cash and short-term investments	56	[1]
Fuel derivative contracts, net	109	[1]
Fair value of assets and liabilities measured on recurring basis	5,205
Level 2 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Level 2 [Member] | US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	1,512	[1],[2]
Level 2 [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	170	[1],[2]
Level 2 [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	2,750	[1],[2]
Level 2 [Member] | Bank Notes/Certificates of Deposit/Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	608	[1],[2]
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Restricted cash and short-term investments	0	[1]
Fuel derivative contracts, net	0	[1]
Fair value of assets and liabilities measured on recurring basis	0
Level 3 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Level 3 [Member] | US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Level 3 [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Level 3 [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
Level 3 [Member] | Bank Notes/Certificates of Deposit/Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[2]
AA [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash and short-term investments	702		850
Level 1 to Level 2 transfer amount	56
AA [Member] | Corporate Obligations [Member] | Maturity Dates Exceeding One Year [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	2,100
AA [Member] | Bank Notes/Certificates of Deposit/Time Deposits [Member] | Maturity Dates Exceeding One Year [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	250
AA [Member] | Government Agency Investments [Member] | Maturity Dates Exceeding One Year [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	511
AA [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	5,162	[1],[3]
Restricted cash and short-term investments	702	[1]
Fuel derivative contracts, net	109	[1]
Fair value of assets and liabilities measured on recurring basis	5,973
AA [Member] | Estimate of Fair Value Measurement [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	323	[1],[3]
AA [Member] | Estimate of Fair Value Measurement [Member] | US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	1,312	[1],[3]
AA [Member] | Estimate of Fair Value Measurement [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	170	[1],[3]
AA [Member] | Estimate of Fair Value Measurement [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	2,750	[1],[3]
AA [Member] | Estimate of Fair Value Measurement [Member] | Bank Notes/Certificates of Deposit/Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	607	[1],[3]
AA [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	323	[1],[3]
Restricted cash and short-term investments	646	[1]
Fuel derivative contracts, net	0	[1]
Fair value of assets and liabilities measured on recurring basis	969
AA [Member] | Level 1 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	323	[1],[3]
AA [Member] | Level 1 [Member] | US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
AA [Member] | Level 1 [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
AA [Member] | Level 1 [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
AA [Member] | Level 1 [Member] | Bank Notes/Certificates of Deposit/Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
AA [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	4,839	[1],[3]
Restricted cash and short-term investments	56	[1]
Fuel derivative contracts, net	109	[1]
Fair value of assets and liabilities measured on recurring basis	5,004
AA [Member] | Level 2 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
AA [Member] | Level 2 [Member] | US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	1,312	[1],[3]
AA [Member] | Level 2 [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	170	[1],[3]
AA [Member] | Level 2 [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	2,750	[1],[3]
AA [Member] | Level 2 [Member] | Bank Notes/Certificates of Deposit/Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	607	[1],[3]
AA [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
Restricted cash and short-term investments	0	[1]
Fuel derivative contracts, net	0	[1]
Fair value of assets and liabilities measured on recurring basis	0
AA [Member] | Level 3 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
AA [Member] | Level 3 [Member] | US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
AA [Member] | Level 3 [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
AA [Member] | Level 3 [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	[1],[3]
AA [Member] | Level 3 [Member] | Bank Notes/Certificates of Deposit/Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	$ 0	[1],[3]

[1] Unrealized gains or losses on short-term investments, restricted cash and short-term investments and derivatives qualifying for hedge accounting are recorded in Accumulated other comprehensive income (loss) at each measurement date.

[2] The Company's short-term investments mature in one year or less except for $250 million of Bank notes/Certificates of deposit/Time deposits, $511 million of U.S. Government agency investments and $2.1 billion of Corporate obligations.

[3] American's short-term investments mature in one year or less except for $250 million of Bank notes/Certificates of deposit/Time deposits, $511 million of U.S. Government agency investments and $2.1 billion of Corporate obligations.